[davetex]

http://www.bushnell.com/tactical/rifle-scopes/ar-optics/1-4x-24mm-throw-down-pcl

This Bushnell has a flip up lever to adjust magnification.

Seems like a cool idea if your running 3 gun.

[mylife]

Hi Dave.
That is an interesting design.

[smokingfrog]

That looks like a good idear.